1. Chapter 5 Section 2 Scale Drawings and Models
Learning Objective:
____________________________

2. Vocabulary
Scale drawing/scale model: is used to represent an _________________
_______________________________________
______________________________________
Scale: gives the relationship between ___________________________________
Scale factor: the ratio of a length on a scale drawing or model to the___________________
________________________________________

3. Scale Example: ________________
(One inch represents an actual distance of 3 feet)
______
(1 unit represents an actual distance of 24 units)

4. Scale Factor
Example: Suppose a scale model has a scale of 2 inches = 16 inches. The scale factor is ___ or __
The lengths and widths of objects of a scale drawing or model are ______________ to the lengths and widths of the actual object.

5. Example 1: Find Actual Measurements
A set of landscape plans shows a flower bed that is 6.5 inches wide. The scale on the plans is 1 inch = 4 feet.
What is the width of the actual flower bed?
Let x represent the actual width of the flower bed. Write and solve a proportion.
Plan width----> ______=________<---plan width
Actual width--> <-----actual width
cross products
The actual flower bed width is feet.

6. From the last example, what is the scale factor?
To find the scale factor, write the ratio of 1 inch to 4 feet in simplest form.
_____= _____ Convert 4 feet
to inches
The scale factor is___. That is , each
measurement on the plan is _ the actual measurement.

7. Example 2: Determine the Scale
In a scale model of a roller coaster, the highest hill has a height of 6 inches. If the actual height of the hill is 210 feet, what is the scale of the model?
Model height---> _______=_______<--model height
Actual height---> <--actual height
So, the scale is______=______

8. Your Turn!
On a set of architectural drawings for an office building, the scale is 1/2” = 3 feet. Find the actual length of each room.
Lobby: 2 inches
Cafeteria: 8.25 inches

9. Your Turn, Again!
In an illustration of a honey bee, the length of the bee is 4.8 cm. The actual size of the honeybee is 1.2 cm. What is the scale of the drawing?

10. Questions
More Practice, then homework!